json字符串中key值下划线命名转换为驼峰命名：

例如：

原json串：
String json= "{'user_name':'ok','user_sex':0,'object_info':{'business_code':'0001','business_info':{'business_name':'ok'}}}";
转换为：
String json= "{'userName':'ok','userSex':0,'objectInfo':{'businessCode':'0001','businessInfo':{'businessName':'ok'}}}";

具体工具类如下:

public class JsonUtils {

    public final static void convert(Object json) {
        if (json instanceof JSONArray) {
            JSONArray arr = (JSONArray) json;
            for (Object obj : arr) {
                convert(obj);
            }
        } else if (json instanceof JSONObject) {
            JSONObject jo = (JSONObject) json;
            Set<String> keys = jo.keySet();
            String[] array = keys.toArray(new String[keys.size()]);
            for (String key : array) {
                Object value = jo.get(key);
                String[] key_strs = key.split("_");
                if (key_strs.length > 1) {
                    StringBuilder sb = new StringBuilder();
                    for (int i = 0; i < key_strs.length; i++) {
                        String ks = key_strs[i];
                        if (!"".equals(ks)) {
                            if (i == 0) {
                                sb.append(ks);
                            } else {
                                int c = ks.charAt(0);
                                if (c >= 97 && c <= 122) {
                                    int v = c - 32;
                                    sb.append((char) v);
                                    if (ks.length() > 1) {
                                        sb.append(ks.substring(1));
                                    }
                                } else {
                                    sb.append(ks);
                                }
                            }
                        }
                    }
                    jo.remove(key);
                    jo.put(sb.toString(), value);
                }
                convert(value);
            }
        }
    }

    public final static Object convert(String json) {
        Object obj = JSON.parse(json);
        convert(obj);
        return obj;
    }
}